Hi there.
The only consequential difference between running UltiDev Cassini for debugging as a regular EXE, and registering your app with Cassini service is that when it runs as a service, it runs under Local System account, while when running as an exe, it runs under your user account that is likely to be more powerful. To debug your app with Cassini service, register the app your are debugging with Cassini service and then attach debugger to UltiDevCassiniWebServer2a.exe process.
Please let us know if this information was helpful.
Best regards,
UltiDev Team.
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